The demand for effective information security schemes is increasing day by day, with the exponential growth and use of Internet. Cryptography and Steganography are two popular techniques, which are to be used for effective secret communications. . In this paper I have proposed a scheme, which can encode a text message and transmit it safely to its destination. Moreover the receiver can authenticate the received message to ensure that any intruder has not altered the original message. To facilitate the authentication facility, a hash code will be generated by the original message, which will be sent to the receiver securely. The hash code will be sent to receiver by hiding it into an image using image steganography. The receiver will decrypt the cipher text message to get the plaintext message. After that receiver will calculate the hash code with the received message and will compare this, with the received hash code. If both the hash codes are equal, it means that the received message is the original message. For generating the hash code, I have used SHA-1 method, and also analysed its performance and compared with that of MD5 method.

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Image Steganography Authentication Hash Functions Information Security.